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75#define pr_fmt(fmt) "UDP: " fmt
76
77#include <linux/uaccess.h>
78#include <asm/ioctls.h>
79#include <linux/memblock.h>
80#include <linux/highmem.h>
81#include <linux/swap.h>
82#include <linux/types.h>
83#include <linux/fcntl.h>
84#include <linux/module.h>
85#include <linux/socket.h>
86#include <linux/sockios.h>
87#include <linux/igmp.h>
88#include <linux/inetdevice.h>
89#include <linux/in.h>
90#include <linux/errno.h>
91#include <linux/timer.h>
92#include <linux/mm.h>
93#include <linux/inet.h>
94#include <linux/netdevice.h>
95#include <linux/slab.h>
96#include <net/tcp_states.h>
97#include <linux/skbuff.h>
98#include <linux/proc_fs.h>
99#include <linux/seq_file.h>
100#include <net/net_namespace.h>
101#include <net/icmp.h>
102#include <net/inet_hashtables.h>
103#include <net/ip_tunnels.h>
104#include <net/route.h>
105#include <net/checksum.h>
106#include <net/xfrm.h>
107#include <trace/events/udp.h>
108#include <linux/static_key.h>
109#include <trace/events/skb.h>
110#include <net/busy_poll.h>
111#include "udp_impl.h"
112#include <net/sock_reuseport.h>
113#include <net/addrconf.h>
114#include <net/udp_tunnel.h>
115
116struct udp_table udp_table __read_mostly;
117EXPORT_SYMBOL(udp_table);
118
119long sysctl_udp_mem[3] __read_mostly;
120EXPORT_SYMBOL(sysctl_udp_mem);
121
122atomic_long_t udp_memory_allocated;
123EXPORT_SYMBOL(udp_memory_allocated);
124
125#define MAX_UDP_PORTS 65536
126#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
127
128static int udp_lib_lport_inuse(struct net *net, __u16 num,
129 const struct udp_hslot *hslot,
130 unsigned long *bitmap,
131 struct sock *sk, unsigned int log)
132{
133 struct sock *sk2;
134 kuid_t uid = sock_i_uid(sk);
135
136 sk_for_each(sk2, &hslot->head) {
137 if (net_eq(sock_net(sk2), net) &&
138 sk2 != sk &&
139 (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
140 (!sk2->sk_reuse || !sk->sk_reuse) &&
141 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
142 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
143 inet_rcv_saddr_equal(sk, sk2, true)) {
144 if (sk2->sk_reuseport && sk->sk_reuseport &&
145 !rcu_access_pointer(sk->sk_reuseport_cb) &&
146 uid_eq(uid, sock_i_uid(sk2))) {
147 if (!bitmap)
148 return 0;
149 } else {
150 if (!bitmap)
151 return 1;
152 __set_bit(udp_sk(sk2)->udp_port_hash >> log,
153 bitmap);
154 }
155 }
156 }
157 return 0;
158}
159
160
161
162
163
164static int udp_lib_lport_inuse2(struct net *net, __u16 num,
165 struct udp_hslot *hslot2,
166 struct sock *sk)
167{
168 struct sock *sk2;
169 kuid_t uid = sock_i_uid(sk);
170 int res = 0;
171
172 spin_lock(&hslot2->lock);
173 udp_portaddr_for_each_entry(sk2, &hslot2->head) {
174 if (net_eq(sock_net(sk2), net) &&
175 sk2 != sk &&
176 (udp_sk(sk2)->udp_port_hash == num) &&
177 (!sk2->sk_reuse || !sk->sk_reuse) &&
178 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
179 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
180 inet_rcv_saddr_equal(sk, sk2, true)) {
181 if (sk2->sk_reuseport && sk->sk_reuseport &&
182 !rcu_access_pointer(sk->sk_reuseport_cb) &&
183 uid_eq(uid, sock_i_uid(sk2))) {
184 res = 0;
185 } else {
186 res = 1;
187 }
188 break;
189 }
190 }
191 spin_unlock(&hslot2->lock);
192 return res;
193}
194
195static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
196{
197 struct net *net = sock_net(sk);
198 kuid_t uid = sock_i_uid(sk);
199 struct sock *sk2;
200
201 sk_for_each(sk2, &hslot->head) {
202 if (net_eq(sock_net(sk2), net) &&
203 sk2 != sk &&
204 sk2->sk_family == sk->sk_family &&
205 ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
206 (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) &&
207 (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
208 sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
209 inet_rcv_saddr_equal(sk, sk2, false)) {
210 return reuseport_add_sock(sk, sk2,
211 inet_rcv_saddr_any(sk));
212 }
213 }
214
215 return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
216}
217
218
219
220
221
222
223
224
225
226int udp_lib_get_port(struct sock *sk, unsigned short snum,
227 unsigned int hash2_nulladdr)
228{
229 struct udp_hslot *hslot, *hslot2;
230 struct udp_table *udptable = sk->sk_prot->h.udp_table;
231 int error = 1;
232 struct net *net = sock_net(sk);
233
234 if (!snum) {
235 int low, high, remaining;
236 unsigned int rand;
237 unsigned short first, last;
238 DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
239
240 inet_get_local_port_range(net, &low, &high);
241 remaining = (high - low) + 1;
242
243 rand = prandom_u32();
244 first = reciprocal_scale(rand, remaining) + low;
245
246
247
248 rand = (rand | 1) * (udptable->mask + 1);
249 last = first + udptable->mask + 1;
250 do {
251 hslot = udp_hashslot(udptable, net, first);
252 bitmap_zero(bitmap, PORTS_PER_CHAIN);
253 spin_lock_bh(&hslot->lock);
254 udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
255 udptable->log);
256
257 snum = first;
258
259
260
261
262
263 do {
264 if (low <= snum && snum <= high &&
265 !test_bit(snum >> udptable->log, bitmap) &&
266 !inet_is_local_reserved_port(net, snum))
267 goto found;
268 snum += rand;
269 } while (snum != first);
270 spin_unlock_bh(&hslot->lock);
271 cond_resched();
272 } while (++first != last);
273 goto fail;
274 } else {
275 hslot = udp_hashslot(udptable, net, snum);
276 spin_lock_bh(&hslot->lock);
277 if (hslot->count > 10) {
278 int exist;
279 unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum;
280
281 slot2 &= udptable->mask;
282 hash2_nulladdr &= udptable->mask;
283
284 hslot2 = udp_hashslot2(udptable, slot2);
285 if (hslot->count < hslot2->count)
286 goto scan_primary_hash;
287
288 exist = udp_lib_lport_inuse2(net, snum, hslot2, sk);
289 if (!exist && (hash2_nulladdr != slot2)) {
290 hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
291 exist = udp_lib_lport_inuse2(net, snum, hslot2,
292 sk);
293 }
294 if (exist)
295 goto fail_unlock;
296 else
297 goto found;
298 }
299scan_primary_hash:
300 if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, 0))
301 goto fail_unlock;
302 }
303found:
304 inet_sk(sk)->inet_num = snum;
305 udp_sk(sk)->udp_port_hash = snum;
306 udp_sk(sk)->udp_portaddr_hash ^= snum;
307 if (sk_unhashed(sk)) {
308 if (sk->sk_reuseport &&
309 udp_reuseport_add_sock(sk, hslot)) {
310 inet_sk(sk)->inet_num = 0;
311 udp_sk(sk)->udp_port_hash = 0;
312 udp_sk(sk)->udp_portaddr_hash ^= snum;
313 goto fail_unlock;
314 }
315
316 sk_add_node_rcu(sk, &hslot->head);
317 hslot->count++;
318 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
319
320 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
321 spin_lock(&hslot2->lock);
322 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
323 sk->sk_family == AF_INET6)
324 hlist_add_tail_rcu(&udp_sk(sk)->udp_portaddr_node,
325 &hslot2->head);
326 else
327 hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
328 &hslot2->head);
329 hslot2->count++;
330 spin_unlock(&hslot2->lock);
331 }
332 sock_set_flag(sk, SOCK_RCU_FREE);
333 error = 0;
334fail_unlock:
335 spin_unlock_bh(&hslot->lock);
336fail:
337 return error;
338}
339EXPORT_SYMBOL(udp_lib_get_port);
340
341int udp_v4_get_port(struct sock *sk, unsigned short snum)
342{
343 unsigned int hash2_nulladdr =
344 ipv4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum);
345 unsigned int hash2_partial =
346 ipv4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0);
347
348
349 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
350 return udp_lib_get_port(sk, snum, hash2_nulladdr);
351}
352
353static int compute_score(struct sock *sk, struct net *net,
354 __be32 saddr, __be16 sport,
355 __be32 daddr, unsigned short hnum,
356 int dif, int sdif)
357{
358 int score;
359 struct inet_sock *inet;
360 bool dev_match;
361
362 if (!net_eq(sock_net(sk), net) ||
363 udp_sk(sk)->udp_port_hash != hnum ||
364 ipv6_only_sock(sk))
365 return -1;
366
367 if (sk->sk_rcv_saddr != daddr)
368 return -1;
369
370 score = (sk->sk_family == PF_INET) ? 2 : 1;
371
372 inet = inet_sk(sk);
373 if (inet->inet_daddr) {
374 if (inet->inet_daddr != saddr)
375 return -1;
376 score += 4;
377 }
378
379 if (inet->inet_dport) {
380 if (inet->inet_dport != sport)
381 return -1;
382 score += 4;
383 }
384
385 dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if,
386 dif, sdif);
387 if (!dev_match)
388 return -1;
389 score += 4;
390
391 if (sk->sk_incoming_cpu == raw_smp_processor_id())
392 score++;
393 return score;
394}
395
396static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
397 const __u16 lport, const __be32 faddr,
398 const __be16 fport)
399{
400 static u32 udp_ehash_secret __read_mostly;
401
402 net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret));
403
404 return __inet_ehashfn(laddr, lport, faddr, fport,
405 udp_ehash_secret + net_hash_mix(net));
406}
407
408
409static struct sock *udp4_lib_lookup2(struct net *net,
410 __be32 saddr, __be16 sport,
411 __be32 daddr, unsigned int hnum,
412 int dif, int sdif,
413 struct udp_hslot *hslot2,
414 struct sk_buff *skb)
415{
416 struct sock *sk, *result;
417 int score, badness;
418 u32 hash = 0;
419
420 result = NULL;
421 badness = 0;
422 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
423 score = compute_score(sk, net, saddr, sport,
424 daddr, hnum, dif, sdif);
425 if (score > badness) {
426 if (sk->sk_reuseport) {
427 hash = udp_ehashfn(net, daddr, hnum,
428 saddr, sport);
429 result = reuseport_select_sock(sk, hash, skb,
430 sizeof(struct udphdr));
431 if (result)
432 return result;
433 }
434 badness = score;
435 result = sk;
436 }
437 }
438 return result;
439}
440
441
442
443
444struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
445 __be16 sport, __be32 daddr, __be16 dport, int dif,
446 int sdif, struct udp_table *udptable, struct sk_buff *skb)
447{
448 struct sock *result;
449 unsigned short hnum = ntohs(dport);
450 unsigned int hash2, slot2;
451 struct udp_hslot *hslot2;
452
453 hash2 = ipv4_portaddr_hash(net, daddr, hnum);
454 slot2 = hash2 & udptable->mask;
455 hslot2 = &udptable->hash2[slot2];
456
457 result = udp4_lib_lookup2(net, saddr, sport,
458 daddr, hnum, dif, sdif,
459 hslot2, skb);
460 if (!result) {
461 hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
462 slot2 = hash2 & udptable->mask;
463 hslot2 = &udptable->hash2[slot2];
464
465 result = udp4_lib_lookup2(net, saddr, sport,
466 htonl(INADDR_ANY), hnum, dif, sdif,
467 hslot2, skb);
468 }
469 if (IS_ERR(result))
470 return NULL;
471 return result;
472}
473EXPORT_SYMBOL_GPL(__udp4_lib_lookup);
474
475static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
476 __be16 sport, __be16 dport,
477 struct udp_table *udptable)
478{
479 const struct iphdr *iph = ip_hdr(skb);
480
481 return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
482 iph->daddr, dport, inet_iif(skb),
483 inet_sdif(skb), udptable, skb);
484}
485
486struct sock *udp4_lib_lookup_skb(struct sk_buff *skb,
487 __be16 sport, __be16 dport)
488{
489 const struct iphdr *iph = ip_hdr(skb);
490
491 return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
492 iph->daddr, dport, inet_iif(skb),
493 inet_sdif(skb), &udp_table, NULL);
494}
495EXPORT_SYMBOL_GPL(udp4_lib_lookup_skb);
496
497
498
499
500#if IS_ENABLED(CONFIG_NF_TPROXY_IPV4) || IS_ENABLED(CONFIG_NF_SOCKET_IPV4)
501struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
502 __be32 daddr, __be16 dport, int dif)
503{
504 struct sock *sk;
505
506 sk = __udp4_lib_lookup(net, saddr, sport, daddr, dport,
507 dif, 0, &udp_table, NULL);
508 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
509 sk = NULL;
510 return sk;
511}
512EXPORT_SYMBOL_GPL(udp4_lib_lookup);
513#endif
514
515static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
516 __be16 loc_port, __be32 loc_addr,
517 __be16 rmt_port, __be32 rmt_addr,
518 int dif, int sdif, unsigned short hnum)
519{
520 struct inet_sock *inet = inet_sk(sk);
521
522 if (!net_eq(sock_net(sk), net) ||
523 udp_sk(sk)->udp_port_hash != hnum ||
524 (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
525 (inet->inet_dport != rmt_port && inet->inet_dport) ||
526 (inet->inet_rcv_saddr && inet->inet_rcv_saddr != loc_addr) ||
527 ipv6_only_sock(sk) ||
528 !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
529 return false;
530 if (!ip_mc_sf_allow(sk, loc_addr, rmt_addr, dif, sdif))
531 return false;
532 return true;
533}
534
535DEFINE_STATIC_KEY_FALSE(udp_encap_needed_key);
536void udp_encap_enable(void)
537{
538 static_branch_inc(&udp_encap_needed_key);
539}
540EXPORT_SYMBOL(udp_encap_enable);
541
542
543
544
545static int __udp4_lib_err_encap_no_sk(struct sk_buff *skb, u32 info)
546{
547 int i;
548
549 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
550 int (*handler)(struct sk_buff *skb, u32 info);
551 const struct ip_tunnel_encap_ops *encap;
552
553 encap = rcu_dereference(iptun_encaps[i]);
554 if (!encap)
555 continue;
556 handler = encap->err_handler;
557 if (handler && !handler(skb, info))
558 return 0;
559 }
560
561 return -ENOENT;
562}
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581static struct sock *__udp4_lib_err_encap(struct net *net,
582 const struct iphdr *iph,
583 struct udphdr *uh,
584 struct udp_table *udptable,
585 struct sk_buff *skb, u32 info)
586{
587 int network_offset, transport_offset;
588 struct sock *sk;
589
590 network_offset = skb_network_offset(skb);
591 transport_offset = skb_transport_offset(skb);
592
593
594 skb_reset_network_header(skb);
595
596
597 skb_set_transport_header(skb, iph->ihl << 2);
598
599 sk = __udp4_lib_lookup(net, iph->daddr, uh->source,
600 iph->saddr, uh->dest, skb->dev->ifindex, 0,
601 udptable, NULL);
602 if (sk) {
603 int (*lookup)(struct sock *sk, struct sk_buff *skb);
604 struct udp_sock *up = udp_sk(sk);
605
606 lookup = READ_ONCE(up->encap_err_lookup);
607 if (!lookup || lookup(sk, skb))
608 sk = NULL;
609 }
610
611 if (!sk)
612 sk = ERR_PTR(__udp4_lib_err_encap_no_sk(skb, info));
613
614 skb_set_transport_header(skb, transport_offset);
615 skb_set_network_header(skb, network_offset);
616
617 return sk;
618}
619
620
621
622
623
624
625
626
627
628
629
630
631int __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
632{
633 struct inet_sock *inet;
634 const struct iphdr *iph = (const struct iphdr *)skb->data;
635 struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2));
636 const int type = icmp_hdr(skb)->type;
637 const int code = icmp_hdr(skb)->code;
638 bool tunnel = false;
639 struct sock *sk;
640 int harderr;
641 int err;
642 struct net *net = dev_net(skb->dev);
643
644 sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
645 iph->saddr, uh->source, skb->dev->ifindex,
646 inet_sdif(skb), udptable, NULL);
647 if (!sk) {
648
649 sk = ERR_PTR(-ENOENT);
650 if (static_branch_unlikely(&udp_encap_needed_key)) {
651 sk = __udp4_lib_err_encap(net, iph, uh, udptable, skb,
652 info);
653 if (!sk)
654 return 0;
655 }
656
657 if (IS_ERR(sk)) {
658 __ICMP_INC_STATS(net, ICMP_MIB_INERRORS);
659 return PTR_ERR(sk);
660 }
661
662 tunnel = true;
663 }
664
665 err = 0;
666 harderr = 0;
667 inet = inet_sk(sk);
668
669 switch (type) {
670 default:
671 case ICMP_TIME_EXCEEDED:
672 err = EHOSTUNREACH;
673 break;
674 case ICMP_SOURCE_QUENCH:
675 goto out;
676 case ICMP_PARAMETERPROB:
677 err = EPROTO;
678 harderr = 1;
679 break;
680 case ICMP_DEST_UNREACH:
681 if (code == ICMP_FRAG_NEEDED) {
682 ipv4_sk_update_pmtu(skb, sk, info);
683 if (inet->pmtudisc != IP_PMTUDISC_DONT) {
684 err = EMSGSIZE;
685 harderr = 1;
686 break;
687 }
688 goto out;
689 }
690 err = EHOSTUNREACH;
691 if (code <= NR_ICMP_UNREACH) {
692 harderr = icmp_err_convert[code].fatal;
693 err = icmp_err_convert[code].errno;
694 }
695 break;
696 case ICMP_REDIRECT:
697 ipv4_sk_redirect(skb, sk);
698 goto out;
699 }
700
701
702
703
704
705 if (tunnel) {
706
707 goto out;
708 }
709 if (!inet->recverr) {
710 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
711 goto out;
712 } else
713 ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1));
714
715 sk->sk_err = err;
716 sk->sk_error_report(sk);
717out:
718 return 0;
719}
720
721int udp_err(struct sk_buff *skb, u32 info)
722{
723 return __udp4_lib_err(skb, info, &udp_table);
724}
725
726
727
728
729void udp_flush_pending_frames(struct sock *sk)
730{
731 struct udp_sock *up = udp_sk(sk);
732
733 if (up->pending) {
734 up->len = 0;
735 up->pending = 0;
736 ip_flush_pending_frames(sk);
737 }
738}
739EXPORT_SYMBOL(udp_flush_pending_frames);
740
741
742
743
744
745
746
747
748void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst)
749{
750 struct udphdr *uh = udp_hdr(skb);
751 int offset = skb_transport_offset(skb);
752 int len = skb->len - offset;
753 int hlen = len;
754 __wsum csum = 0;
755
756 if (!skb_has_frag_list(skb)) {
757
758
759
760 skb->csum_start = skb_transport_header(skb) - skb->head;
761 skb->csum_offset = offsetof(struct udphdr, check);
762 uh->check = ~csum_tcpudp_magic(src, dst, len,
763 IPPROTO_UDP, 0);
764 } else {
765 struct sk_buff *frags;
766
767
768
769
770
771
772 skb_walk_frags(skb, frags) {
773 csum = csum_add(csum, frags->csum);
774 hlen -= frags->len;
775 }
776
777 csum = skb_checksum(skb, offset, hlen, csum);
778 skb->ip_summed = CHECKSUM_NONE;
779
780 uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum);
781 if (uh->check == 0)
782 uh->check = CSUM_MANGLED_0;
783 }
784}
785EXPORT_SYMBOL_GPL(udp4_hwcsum);
786
787
788
789
790void udp_set_csum(bool nocheck, struct sk_buff *skb,
791 __be32 saddr, __be32 daddr, int len)
792{
793 struct udphdr *uh = udp_hdr(skb);
794
795 if (nocheck) {
796 uh->check = 0;
797 } else if (skb_is_gso(skb)) {
798 uh->check = ~udp_v4_check(len, saddr, daddr, 0);
799 } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
800 uh->check = 0;
801 uh->check = udp_v4_check(len, saddr, daddr, lco_csum(skb));
802 if (uh->check == 0)
803 uh->check = CSUM_MANGLED_0;
804 } else {
805 skb->ip_summed = CHECKSUM_PARTIAL;
806 skb->csum_start = skb_transport_header(skb) - skb->head;
807 skb->csum_offset = offsetof(struct udphdr, check);
808 uh->check = ~udp_v4_check(len, saddr, daddr, 0);
809 }
810}
811EXPORT_SYMBOL(udp_set_csum);
812
813static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4,
814 struct inet_cork *cork)
815{
816 struct sock *sk = skb->sk;
817 struct inet_sock *inet = inet_sk(sk);
818 struct udphdr *uh;
819 int err = 0;
820 int is_udplite = IS_UDPLITE(sk);
821 int offset = skb_transport_offset(skb);
822 int len = skb->len - offset;
823 __wsum csum = 0;
824
825
826
827
828 uh = udp_hdr(skb);
829 uh->source = inet->inet_sport;
830 uh->dest = fl4->fl4_dport;
831 uh->len = htons(len);
832 uh->check = 0;
833
834 if (cork->gso_size) {
835 const int hlen = skb_network_header_len(skb) +
836 sizeof(struct udphdr);
837
838 if (hlen + cork->gso_size > cork->fragsize) {
839 kfree_skb(skb);
840 return -EINVAL;
841 }
842 if (skb->len > cork->gso_size * UDP_MAX_SEGMENTS) {
843 kfree_skb(skb);
844 return -EINVAL;
845 }
846 if (sk->sk_no_check_tx) {
847 kfree_skb(skb);
848 return -EINVAL;
849 }
850 if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
851 dst_xfrm(skb_dst(skb))) {
852 kfree_skb(skb);
853 return -EIO;
854 }
855
856 skb_shinfo(skb)->gso_size = cork->gso_size;
857 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
858 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(len - sizeof(uh),
859 cork->gso_size);
860 goto csum_partial;
861 }
862
863 if (is_udplite)
864 csum = udplite_csum(skb);
865
866 else if (sk->sk_no_check_tx) {
867
868 skb->ip_summed = CHECKSUM_NONE;
869 goto send;
870
871 } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
872csum_partial:
873
874 udp4_hwcsum(skb, fl4->saddr, fl4->daddr);
875 goto send;
876
877 } else
878 csum = udp_csum(skb);
879
880
881 uh->check = csum_tcpudp_magic(fl4->saddr, fl4->daddr, len,
882 sk->sk_protocol, csum);
883 if (uh->check == 0)
884 uh->check = CSUM_MANGLED_0;
885
886send:
887 err = ip_send_skb(sock_net(sk), skb);
888 if (err) {
889 if (err == -ENOBUFS && !inet->recverr) {
890 UDP_INC_STATS(sock_net(sk),
891 UDP_MIB_SNDBUFERRORS, is_udplite);
892 err = 0;
893 }
894 } else
895 UDP_INC_STATS(sock_net(sk),
896 UDP_MIB_OUTDATAGRAMS, is_udplite);
897 return err;
898}
899
900
901
902
903int udp_push_pending_frames(struct sock *sk)
904{
905 struct udp_sock *up = udp_sk(sk);
906 struct inet_sock *inet = inet_sk(sk);
907 struct flowi4 *fl4 = &inet->cork.fl.u.ip4;
908 struct sk_buff *skb;
909 int err = 0;
910
911 skb = ip_finish_skb(sk, fl4);
912 if (!skb)
913 goto out;
914
915 err = udp_send_skb(skb, fl4, &inet->cork.base);
916
917out:
918 up->len = 0;
919 up->pending = 0;
920 return err;
921}
922EXPORT_SYMBOL(udp_push_pending_frames);
923
924static int __udp_cmsg_send(struct cmsghdr *cmsg, u16 *gso_size)
925{
926 switch (cmsg->cmsg_type) {
927 case UDP_SEGMENT:
928 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u16)))
929 return -EINVAL;
930 *gso_size = *(__u16 *)CMSG_DATA(cmsg);
931 return 0;
932 default:
933 return -EINVAL;
934 }
935}
936
937int udp_cmsg_send(struct sock *sk, struct msghdr *msg, u16 *gso_size)
938{
939 struct cmsghdr *cmsg;
940 bool need_ip = false;
941 int err;
942
943 for_each_cmsghdr(cmsg, msg) {
944 if (!CMSG_OK(msg, cmsg))
945 return -EINVAL;
946
947 if (cmsg->cmsg_level != SOL_UDP) {
948 need_ip = true;
949 continue;
950 }
951
952 err = __udp_cmsg_send(cmsg, gso_size);
953 if (err)
954 return err;
955 }
956
957 return need_ip;
958}
959EXPORT_SYMBOL_GPL(udp_cmsg_send);
960
961int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
962{
963 struct inet_sock *inet = inet_sk(sk);
964 struct udp_sock *up = udp_sk(sk);
965 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
966 struct flowi4 fl4_stack;
967 struct flowi4 *fl4;
968 int ulen = len;
969 struct ipcm_cookie ipc;
970 struct rtable *rt = NULL;
971 int free = 0;
972 int connected = 0;
973 __be32 daddr, faddr, saddr;
974 __be16 dport;
975 u8 tos;
976 int err, is_udplite = IS_UDPLITE(sk);
977 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE;
978 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
979 struct sk_buff *skb;
980 struct ip_options_data opt_copy;
981
982 if (len > 0xFFFF)
983 return -EMSGSIZE;
984
985
986
987
988
989 if (msg->msg_flags & MSG_OOB)
990 return -EOPNOTSUPP;
991
992 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
993
994 fl4 = &inet->cork.fl.u.ip4;
995 if (up->pending) {
996
997
998
999
1000 lock_sock(sk);
1001 if (likely(up->pending)) {
1002 if (unlikely(up->pending != AF_INET)) {
1003 release_sock(sk);
1004 return -EINVAL;
1005 }
1006 goto do_append_data;
1007 }
1008 release_sock(sk);
1009 }
1010 ulen += sizeof(struct udphdr);
1011
1012
1013
1014
1015 if (usin) {
1016 if (msg->msg_namelen < sizeof(*usin))
1017 return -EINVAL;
1018 if (usin->sin_family != AF_INET) {
1019 if (usin->sin_family != AF_UNSPEC)
1020 return -EAFNOSUPPORT;
1021 }
1022
1023 daddr = usin->sin_addr.s_addr;
1024 dport = usin->sin_port;
1025 if (dport == 0)
1026 return -EINVAL;
1027 } else {
1028 if (sk->sk_state != TCP_ESTABLISHED)
1029 return -EDESTADDRREQ;
1030 daddr = inet->inet_daddr;
1031 dport = inet->inet_dport;
1032
1033
1034
1035 connected = 1;
1036 }
1037
1038 ipcm_init_sk(&ipc, inet);
1039 ipc.gso_size = up->gso_size;
1040
1041 if (msg->msg_controllen) {
1042 err = udp_cmsg_send(sk, msg, &ipc.gso_size);
1043 if (err > 0)
1044 err = ip_cmsg_send(sk, msg, &ipc,
1045 sk->sk_family == AF_INET6);
1046 if (unlikely(err < 0)) {
1047 kfree(ipc.opt);
1048 return err;
1049 }
1050 if (ipc.opt)
1051 free = 1;
1052 connected = 0;
1053 }
1054 if (!ipc.opt) {
1055 struct ip_options_rcu *inet_opt;
1056
1057 rcu_read_lock();
1058 inet_opt = rcu_dereference(inet->inet_opt);
1059 if (inet_opt) {
1060 memcpy(&opt_copy, inet_opt,
1061 sizeof(*inet_opt) + inet_opt->opt.optlen);
1062 ipc.opt = &opt_copy.opt;
1063 }
1064 rcu_read_unlock();
1065 }
1066
1067 if (cgroup_bpf_enabled && !connected) {
1068 err = BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk,
1069 (struct sockaddr *)usin, &ipc.addr);
1070 if (err)
1071 goto out_free;
1072 if (usin) {
1073 if (usin->sin_port == 0) {
1074
1075 err = -EINVAL;
1076 goto out_free;
1077 }
1078 daddr = usin->sin_addr.s_addr;
1079 dport = usin->sin_port;
1080 }
1081 }
1082
1083 saddr = ipc.addr;
1084 ipc.addr = faddr = daddr;
1085
1086 if (ipc.opt && ipc.opt->opt.srr) {
1087 if (!daddr) {
1088 err = -EINVAL;
1089 goto out_free;
1090 }
1091 faddr = ipc.opt->opt.faddr;
1092 connected = 0;
1093 }
1094 tos = get_rttos(&ipc, inet);
1095 if (sock_flag(sk, SOCK_LOCALROUTE) ||
1096 (msg->msg_flags & MSG_DONTROUTE) ||
1097 (ipc.opt && ipc.opt->opt.is_strictroute)) {
1098 tos |= RTO_ONLINK;
1099 connected = 0;
1100 }
1101
1102 if (ipv4_is_multicast(daddr)) {
1103 if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
1104 ipc.oif = inet->mc_index;
1105 if (!saddr)
1106 saddr = inet->mc_addr;
1107 connected = 0;
1108 } else if (!ipc.oif) {
1109 ipc.oif = inet->uc_index;
1110 } else if (ipv4_is_lbcast(daddr) && inet->uc_index) {
1111
1112
1113
1114
1115
1116
1117 if (ipc.oif != inet->uc_index &&
1118 ipc.oif == l3mdev_master_ifindex_by_index(sock_net(sk),
1119 inet->uc_index)) {
1120 ipc.oif = inet->uc_index;
1121 }
1122 }
1123
1124 if (connected)
1125 rt = (struct rtable *)sk_dst_check(sk, 0);
1126
1127 if (!rt) {
1128 struct net *net = sock_net(sk);
1129 __u8 flow_flags = inet_sk_flowi_flags(sk);
1130
1131 fl4 = &fl4_stack;
1132
1133 flowi4_init_output(fl4, ipc.oif, sk->sk_mark, tos,
1134 RT_SCOPE_UNIVERSE, sk->sk_protocol,
1135 flow_flags,
1136 faddr, saddr, dport, inet->inet_sport,
1137 sk->sk_uid);
1138
1139 security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
1140 rt = ip_route_output_flow(net, fl4, sk);
1141 if (IS_ERR(rt)) {
1142 err = PTR_ERR(rt);
1143 rt = NULL;
1144 if (err == -ENETUNREACH)
1145 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
1146 goto out;
1147 }
1148
1149 err = -EACCES;
1150 if ((rt->rt_flags & RTCF_BROADCAST) &&
1151 !sock_flag(sk, SOCK_BROADCAST))
1152 goto out;
1153 if (connected)
1154 sk_dst_set(sk, dst_clone(&rt->dst));
1155 }
1156
1157 if (msg->msg_flags&MSG_CONFIRM)
1158 goto do_confirm;
1159back_from_confirm:
1160
1161 saddr = fl4->saddr;
1162 if (!ipc.addr)
1163 daddr = ipc.addr = fl4->daddr;
1164
1165
1166 if (!corkreq) {
1167 struct inet_cork cork;
1168
1169 skb = ip_make_skb(sk, fl4, getfrag, msg, ulen,
1170 sizeof(struct udphdr), &ipc, &rt,
1171 &cork, msg->msg_flags);
1172 err = PTR_ERR(skb);
1173 if (!IS_ERR_OR_NULL(skb))
1174 err = udp_send_skb(skb, fl4, &cork);
1175 goto out;
1176 }
1177
1178 lock_sock(sk);
1179 if (unlikely(up->pending)) {
1180
1181
1182 release_sock(sk);
1183
1184 net_dbg_ratelimited("socket already corked\n");
1185 err = -EINVAL;
1186 goto out;
1187 }
1188
1189
1190
1191 fl4 = &inet->cork.fl.u.ip4;
1192 fl4->daddr = daddr;
1193 fl4->saddr = saddr;
1194 fl4->fl4_dport = dport;
1195 fl4->fl4_sport = inet->inet_sport;
1196 up->pending = AF_INET;
1197
1198do_append_data:
1199 up->len += ulen;
1200 err = ip_append_data(sk, fl4, getfrag, msg, ulen,
1201 sizeof(struct udphdr), &ipc, &rt,
1202 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
1203 if (err)
1204 udp_flush_pending_frames(sk);
1205 else if (!corkreq)
1206 err = udp_push_pending_frames(sk);
1207 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1208 up->pending = 0;
1209 release_sock(sk);
1210
1211out:
1212 ip_rt_put(rt);
1213out_free:
1214 if (free)
1215 kfree(ipc.opt);
1216 if (!err)
1217 return len;
1218
1219
1220
1221
1222
1223
1224
1225 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
1226 UDP_INC_STATS(sock_net(sk),
1227 UDP_MIB_SNDBUFERRORS, is_udplite);
1228 }
1229 return err;
1230
1231do_confirm:
1232 if (msg->msg_flags & MSG_PROBE)
1233 dst_confirm_neigh(&rt->dst, &fl4->daddr);
1234 if (!(msg->msg_flags&MSG_PROBE) || len)
1235 goto back_from_confirm;
1236 err = 0;
1237 goto out;
1238}
1239EXPORT_SYMBOL(udp_sendmsg);
1240
1241int udp_sendpage(struct sock *sk, struct page *page, int offset,
1242 size_t size, int flags)
1243{
1244 struct inet_sock *inet = inet_sk(sk);
1245 struct udp_sock *up = udp_sk(sk);
1246 int ret;
1247
1248 if (flags & MSG_SENDPAGE_NOTLAST)
1249 flags |= MSG_MORE;
1250
1251 if (!up->pending) {
1252 struct msghdr msg = { .msg_flags = flags|MSG_MORE };
1253
1254
1255
1256
1257
1258 ret = udp_sendmsg(sk, &msg, 0);
1259 if (ret < 0)
1260 return ret;
1261 }
1262
1263 lock_sock(sk);
1264
1265 if (unlikely(!up->pending)) {
1266 release_sock(sk);
1267
1268 net_dbg_ratelimited("cork failed\n");
1269 return -EINVAL;
1270 }
1271
1272 ret = ip_append_page(sk, &inet->cork.fl.u.ip4,
1273 page, offset, size, flags);
1274 if (ret == -EOPNOTSUPP) {
1275 release_sock(sk);
1276 return sock_no_sendpage(sk->sk_socket, page, offset,
1277 size, flags);
1278 }
1279 if (ret < 0) {
1280 udp_flush_pending_frames(sk);
1281 goto out;
1282 }
1283
1284 up->len += size;
1285 if (!(up->corkflag || (flags&MSG_MORE)))
1286 ret = udp_push_pending_frames(sk);
1287 if (!ret)
1288 ret = size;
1289out:
1290 release_sock(sk);
1291 return ret;
1292}
1293
1294#define UDP_SKB_IS_STATELESS 0x80000000
1295
1296static void udp_set_dev_scratch(struct sk_buff *skb)
1297{
1298 struct udp_dev_scratch *scratch = udp_skb_scratch(skb);
1299
1300 BUILD_BUG_ON(sizeof(struct udp_dev_scratch) > sizeof(long));
1301 scratch->_tsize_state = skb->truesize;
1302#if BITS_PER_LONG == 64
1303 scratch->len = skb->len;
1304 scratch->csum_unnecessary = !!skb_csum_unnecessary(skb);
1305 scratch->is_linear = !skb_is_nonlinear(skb);
1306#endif
1307
1308
1309
1310
1311 if (likely(!skb_sec_path(skb)))
1312 scratch->_tsize_state |= UDP_SKB_IS_STATELESS;
1313}
1314
1315static int udp_skb_truesize(struct sk_buff *skb)
1316{
1317 return udp_skb_scratch(skb)->_tsize_state & ~UDP_SKB_IS_STATELESS;
1318}
1319
1320static bool udp_skb_has_head_state(struct sk_buff *skb)
1321{
1322 return !(udp_skb_scratch(skb)->_tsize_state & UDP_SKB_IS_STATELESS);
1323}
1324
1325
1326static void udp_rmem_release(struct sock *sk, int size, int partial,
1327 bool rx_queue_lock_held)
1328{
1329 struct udp_sock *up = udp_sk(sk);
1330 struct sk_buff_head *sk_queue;
1331 int amt;
1332
1333 if (likely(partial)) {
1334 up->forward_deficit += size;
1335 size = up->forward_deficit;
1336 if (size < (sk->sk_rcvbuf >> 2))
1337 return;
1338 } else {
1339 size += up->forward_deficit;
1340 }
1341 up->forward_deficit = 0;
1342
1343
1344
1345
1346 sk_queue = &sk->sk_receive_queue;
1347 if (!rx_queue_lock_held)
1348 spin_lock(&sk_queue->lock);
1349
1350
1351 sk->sk_forward_alloc += size;
1352 amt = (sk->sk_forward_alloc - partial) & ~(SK_MEM_QUANTUM - 1);
1353 sk->sk_forward_alloc -= amt;
1354
1355 if (amt)
1356 __sk_mem_reduce_allocated(sk, amt >> SK_MEM_QUANTUM_SHIFT);
1357
1358 atomic_sub(size, &sk->sk_rmem_alloc);
1359
1360
1361 skb_queue_splice_tail_init(sk_queue, &up->reader_queue);
1362
1363 if (!rx_queue_lock_held)
1364 spin_unlock(&sk_queue->lock);
1365}
1366
1367
1368
1369
1370
1371
1372void udp_skb_destructor(struct sock *sk, struct sk_buff *skb)
1373{
1374 prefetch(&skb->data);
1375 udp_rmem_release(sk, udp_skb_truesize(skb), 1, false);
1376}
1377EXPORT_SYMBOL(udp_skb_destructor);
1378
1379
1380static void udp_skb_dtor_locked(struct sock *sk, struct sk_buff *skb)
1381{
1382 prefetch(&skb->data);
1383 udp_rmem_release(sk, udp_skb_truesize(skb), 1, true);
1384}
1385
1386
1387
1388
1389
1390
1391
1392
1393static int udp_busylocks_log __read_mostly;
1394static spinlock_t *udp_busylocks __read_mostly;
1395
1396static spinlock_t *busylock_acquire(void *ptr)
1397{
1398 spinlock_t *busy;
1399
1400 busy = udp_busylocks + hash_ptr(ptr, udp_busylocks_log);
1401 spin_lock(busy);
1402 return busy;
1403}
1404
1405static void busylock_release(spinlock_t *busy)
1406{
1407 if (busy)
1408 spin_unlock(busy);
1409}
1410
1411int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb)
1412{
1413 struct sk_buff_head *list = &sk->sk_receive_queue;
1414 int rmem, delta, amt, err = -ENOMEM;
1415 spinlock_t *busy = NULL;
1416 int size;
1417
1418
1419
1420
1421 rmem = atomic_read(&sk->sk_rmem_alloc);
1422 if (rmem > sk->sk_rcvbuf)
1423 goto drop;
1424
1425
1426
1427
1428
1429
1430
1431 if (rmem > (sk->sk_rcvbuf >> 1)) {
1432 skb_condense(skb);
1433
1434 busy = busylock_acquire(sk);
1435 }
1436 size = skb->truesize;
1437 udp_set_dev_scratch(skb);
1438
1439
1440
1441
1442 rmem = atomic_add_return(size, &sk->sk_rmem_alloc);
1443 if (rmem > (size + sk->sk_rcvbuf))
1444 goto uncharge_drop;
1445
1446 spin_lock(&list->lock);
1447 if (size >= sk->sk_forward_alloc) {
1448 amt = sk_mem_pages(size);
1449 delta = amt << SK_MEM_QUANTUM_SHIFT;
1450 if (!__sk_mem_raise_allocated(sk, delta, amt, SK_MEM_RECV)) {
1451 err = -ENOBUFS;
1452 spin_unlock(&list->lock);
1453 goto uncharge_drop;
1454 }
1455
1456 sk->sk_forward_alloc += delta;
1457 }
1458
1459 sk->sk_forward_alloc -= size;
1460
1461
1462
1463
1464 sock_skb_set_dropcount(sk, skb);
1465
1466 __skb_queue_tail(list, skb);
1467 spin_unlock(&list->lock);
1468
1469 if (!sock_flag(sk, SOCK_DEAD))
1470 sk->sk_data_ready(sk);
1471
1472 busylock_release(busy);
1473 return 0;
1474
1475uncharge_drop:
1476 atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1477
1478drop:
1479 atomic_inc(&sk->sk_drops);
1480 busylock_release(busy);
1481 return err;
1482}
1483EXPORT_SYMBOL_GPL(__udp_enqueue_schedule_skb);
1484
1485void udp_destruct_sock(struct sock *sk)
1486{
1487
1488 struct udp_sock *up = udp_sk(sk);
1489 unsigned int total = 0;
1490 struct sk_buff *skb;
1491
1492 skb_queue_splice_tail_init(&sk->sk_receive_queue, &up->reader_queue);
1493 while ((skb = __skb_dequeue(&up->reader_queue)) != NULL) {
1494 total += skb->truesize;
1495 kfree_skb(skb);
1496 }
1497 udp_rmem_release(sk, total, 0, true);
1498
1499 inet_sock_destruct(sk);
1500}
1501EXPORT_SYMBOL_GPL(udp_destruct_sock);
1502
1503int udp_init_sock(struct sock *sk)
1504{
1505 skb_queue_head_init(&udp_sk(sk)->reader_queue);
1506 sk->sk_destruct = udp_destruct_sock;
1507 return 0;
1508}
1509EXPORT_SYMBOL_GPL(udp_init_sock);
1510
1511void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len)
1512{
1513 if (unlikely(READ_ONCE(sk->sk_peek_off) >= 0)) {
1514 bool slow = lock_sock_fast(sk);
1515
1516 sk_peek_offset_bwd(sk, len);
1517 unlock_sock_fast(sk, slow);
1518 }
1519
1520 if (!skb_unref(skb))
1521 return;
1522
1523
1524
1525
1526 if (unlikely(udp_skb_has_head_state(skb)))
1527 skb_release_head_state(skb);
1528 __consume_stateless_skb(skb);
1529}
1530EXPORT_SYMBOL_GPL(skb_consume_udp);
1531
1532static struct sk_buff *__first_packet_length(struct sock *sk,
1533 struct sk_buff_head *rcvq,
1534 int *total)
1535{
1536 struct sk_buff *skb;
1537
1538 while ((skb = skb_peek(rcvq)) != NULL) {
1539 if (udp_lib_checksum_complete(skb)) {
1540 __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS,
1541 IS_UDPLITE(sk));
1542 __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
1543 IS_UDPLITE(sk));
1544 atomic_inc(&sk->sk_drops);
1545 __skb_unlink(skb, rcvq);
1546 *total += skb->truesize;
1547 kfree_skb(skb);
1548 } else {
1549
1550
1551
1552 udp_set_dev_scratch(skb);
1553 break;
1554 }
1555 }
1556 return skb;
1557}
1558
1559
1560
1561
1562
1563
1564
1565
1566static int first_packet_length(struct sock *sk)
1567{
1568 struct sk_buff_head *rcvq = &udp_sk(sk)->reader_queue;
1569 struct sk_buff_head *sk_queue = &sk->sk_receive_queue;
1570 struct sk_buff *skb;
1571 int total = 0;
1572 int res;
1573
1574 spin_lock_bh(&rcvq->lock);
1575 skb = __first_packet_length(sk, rcvq, &total);
1576 if (!skb && !skb_queue_empty(sk_queue)) {
1577 spin_lock(&sk_queue->lock);
1578 skb_queue_splice_tail_init(sk_queue, rcvq);
1579 spin_unlock(&sk_queue->lock);
1580
1581 skb = __first_packet_length(sk, rcvq, &total);
1582 }
1583 res = skb ? skb->len : -1;
1584 if (total)
1585 udp_rmem_release(sk, total, 1, false);
1586 spin_unlock_bh(&rcvq->lock);
1587 return res;
1588}
1589
1590
1591
1592
1593
1594int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
1595{
1596 switch (cmd) {
1597 case SIOCOUTQ:
1598 {
1599 int amount = sk_wmem_alloc_get(sk);
1600
1601 return put_user(amount, (int __user *)arg);
1602 }
1603
1604 case SIOCINQ:
1605 {
1606 int amount = max_t(int, 0, first_packet_length(sk));
1607
1608 return put_user(amount, (int __user *)arg);
1609 }
1610
1611 default:
1612 return -ENOIOCTLCMD;
1613 }
1614
1615 return 0;
1616}
1617EXPORT_SYMBOL(udp_ioctl);
1618
1619struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
1620 int noblock, int *off, int *err)
1621{
1622 struct sk_buff_head *sk_queue = &sk->sk_receive_queue;
1623 struct sk_buff_head *queue;
1624 struct sk_buff *last;
1625 long timeo;
1626 int error;
1627
1628 queue = &udp_sk(sk)->reader_queue;
1629 flags |= noblock ? MSG_DONTWAIT : 0;
1630 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1631 do {
1632 struct sk_buff *skb;
1633
1634 error = sock_error(sk);
1635 if (error)
1636 break;
1637
1638 error = -EAGAIN;
1639 do {
1640 spin_lock_bh(&queue->lock);
1641 skb = __skb_try_recv_from_queue(sk, queue, flags,
1642 udp_skb_destructor,
1643 off, err, &last);
1644 if (skb) {
1645 spin_unlock_bh(&queue->lock);
1646 return skb;
1647 }
1648
1649 if (skb_queue_empty(sk_queue)) {
1650 spin_unlock_bh(&queue->lock);
1651 goto busy_check;
1652 }
1653
1654
1655
1656
1657
1658
1659 spin_lock(&sk_queue->lock);
1660 skb_queue_splice_tail_init(sk_queue, queue);
1661
1662 skb = __skb_try_recv_from_queue(sk, queue, flags,
1663 udp_skb_dtor_locked,
1664 off, err, &last);
1665 spin_unlock(&sk_queue->lock);
1666 spin_unlock_bh(&queue->lock);
1667 if (skb)
1668 return skb;
1669
1670busy_check:
1671 if (!sk_can_busy_loop(sk))
1672 break;
1673
1674 sk_busy_loop(sk, flags & MSG_DONTWAIT);
1675 } while (!skb_queue_empty(sk_queue));
1676
1677
1678 } while (timeo &&
1679 !__skb_wait_for_more_packets(sk, &error, &timeo,
1680 (struct sk_buff *)sk_queue));
1681
1682 *err = error;
1683 return NULL;
1684}
1685EXPORT_SYMBOL(__skb_recv_udp);
1686
1687
1688
1689
1690
1691
1692int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
1693 int flags, int *addr_len)
1694{
1695 struct inet_sock *inet = inet_sk(sk);
1696 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
1697 struct sk_buff *skb;
1698 unsigned int ulen, copied;
1699 int off, err, peeking = flags & MSG_PEEK;
1700 int is_udplite = IS_UDPLITE(sk);
1701 bool checksum_valid = false;
1702
1703 if (flags & MSG_ERRQUEUE)
1704 return ip_recv_error(sk, msg, len, addr_len);
1705
1706try_again:
1707 off = sk_peek_offset(sk, flags);
1708 skb = __skb_recv_udp(sk, flags, noblock, &off, &err);
1709 if (!skb)
1710 return err;
1711
1712 ulen = udp_skb_len(skb);
1713 copied = len;
1714 if (copied > ulen - off)
1715 copied = ulen - off;
1716 else if (copied < ulen)
1717 msg->msg_flags |= MSG_TRUNC;
1718
1719
1720
1721
1722
1723
1724
1725 if (copied < ulen || peeking ||
1726 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
1727 checksum_valid = udp_skb_csum_unnecessary(skb) ||
1728 !__udp_lib_checksum_complete(skb);
1729 if (!checksum_valid)
1730 goto csum_copy_err;
1731 }
1732
1733 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
1734 if (udp_skb_is_linear(skb))
1735 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
1736 else
1737 err = skb_copy_datagram_msg(skb, off, msg, copied);
1738 } else {
1739 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
1740
1741 if (err == -EINVAL)
1742 goto csum_copy_err;
1743 }
1744
1745 if (unlikely(err)) {
1746 if (!peeking) {
1747 atomic_inc(&sk->sk_drops);
1748 UDP_INC_STATS(sock_net(sk),
1749 UDP_MIB_INERRORS, is_udplite);
1750 }
1751 kfree_skb(skb);
1752 return err;
1753 }
1754
1755 if (!peeking)
1756 UDP_INC_STATS(sock_net(sk),
1757 UDP_MIB_INDATAGRAMS, is_udplite);
1758
1759 sock_recv_ts_and_drops(msg, sk, skb);
1760
1761
1762 if (sin) {
1763 sin->sin_family = AF_INET;
1764 sin->sin_port = udp_hdr(skb)->source;
1765 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1766 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
1767 *addr_len = sizeof(*sin);
1768
1769 if (cgroup_bpf_enabled)
1770 BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk,
1771 (struct sockaddr *)sin);
1772 }
1773
1774 if (udp_sk(sk)->gro_enabled)
1775 udp_cmsg_recv(msg, sk, skb);
1776
1777 if (inet->cmsg_flags)
1778 ip_cmsg_recv_offset(msg, sk, skb, sizeof(struct udphdr), off);
1779
1780 err = copied;
1781 if (flags & MSG_TRUNC)
1782 err = ulen;
1783
1784 skb_consume_udp(sk, skb, peeking ? -err : err);
1785 return err;
1786
1787csum_copy_err:
1788 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
1789 udp_skb_destructor)) {
1790 UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
1791 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
1792 }
1793 kfree_skb(skb);
1794
1795
1796 cond_resched();
1797 msg->msg_flags &= ~MSG_TRUNC;
1798 goto try_again;
1799}
1800
1801int udp_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
1802{
1803
1804
1805
1806
1807 if (addr_len < sizeof(struct sockaddr_in))
1808 return -EINVAL;
1809
1810 return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr);
1811}
1812EXPORT_SYMBOL(udp_pre_connect);
1813
1814int __udp_disconnect(struct sock *sk, int flags)
1815{
1816 struct inet_sock *inet = inet_sk(sk);
1817
1818
1819
1820
1821 sk->sk_state = TCP_CLOSE;
1822 inet->inet_daddr = 0;
1823 inet->inet_dport = 0;
1824 sock_rps_reset_rxhash(sk);
1825 sk->sk_bound_dev_if = 0;
1826 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
1827 inet_reset_saddr(sk);
1828
1829 if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) {
1830 sk->sk_prot->unhash(sk);
1831 inet->inet_sport = 0;
1832 }
1833 sk_dst_reset(sk);
1834 return 0;
1835}
1836EXPORT_SYMBOL(__udp_disconnect);
1837
1838int udp_disconnect(struct sock *sk, int flags)
1839{
1840 lock_sock(sk);
1841 __udp_disconnect(sk, flags);
1842 release_sock(sk);
1843 return 0;
1844}
1845EXPORT_SYMBOL(udp_disconnect);
1846
1847void udp_lib_unhash(struct sock *sk)
1848{
1849 if (sk_hashed(sk)) {
1850 struct udp_table *udptable = sk->sk_prot->h.udp_table;
1851 struct udp_hslot *hslot, *hslot2;
1852
1853 hslot = udp_hashslot(udptable, sock_net(sk),
1854 udp_sk(sk)->udp_port_hash);
1855 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
1856
1857 spin_lock_bh(&hslot->lock);
1858 if (rcu_access_pointer(sk->sk_reuseport_cb))
1859 reuseport_detach_sock(sk);
1860 if (sk_del_node_init_rcu(sk)) {
1861 hslot->count--;
1862 inet_sk(sk)->inet_num = 0;
1863 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
1864
1865 spin_lock(&hslot2->lock);
1866 hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
1867 hslot2->count--;
1868 spin_unlock(&hslot2->lock);
1869 }
1870 spin_unlock_bh(&hslot->lock);
1871 }
1872}
1873EXPORT_SYMBOL(udp_lib_unhash);
1874
1875
1876
1877
1878void udp_lib_rehash(struct sock *sk, u16 newhash)
1879{
1880 if (sk_hashed(sk)) {
1881 struct udp_table *udptable = sk->sk_prot->h.udp_table;
1882 struct udp_hslot *hslot, *hslot2, *nhslot2;
1883
1884 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
1885 nhslot2 = udp_hashslot2(udptable, newhash);
1886 udp_sk(sk)->udp_portaddr_hash = newhash;
1887
1888 if (hslot2 != nhslot2 ||
1889 rcu_access_pointer(sk->sk_reuseport_cb)) {
1890 hslot = udp_hashslot(udptable, sock_net(sk),
1891 udp_sk(sk)->udp_port_hash);
1892
1893 spin_lock_bh(&hslot->lock);
1894 if (rcu_access_pointer(sk->sk_reuseport_cb))
1895 reuseport_detach_sock(sk);
1896
1897 if (hslot2 != nhslot2) {
1898 spin_lock(&hslot2->lock);
1899 hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
1900 hslot2->count--;
1901 spin_unlock(&hslot2->lock);
1902
1903 spin_lock(&nhslot2->lock);
1904 hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
1905 &nhslot2->head);
1906 nhslot2->count++;
1907 spin_unlock(&nhslot2->lock);
1908 }
1909
1910 spin_unlock_bh(&hslot->lock);
1911 }
1912 }
1913}
1914EXPORT_SYMBOL(udp_lib_rehash);
1915
1916void udp_v4_rehash(struct sock *sk)
1917{
1918 u16 new_hash = ipv4_portaddr_hash(sock_net(sk),
1919 inet_sk(sk)->inet_rcv_saddr,
1920 inet_sk(sk)->inet_num);
1921 udp_lib_rehash(sk, new_hash);
1922}
1923
1924static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
1925{
1926 int rc;
1927
1928 if (inet_sk(sk)->inet_daddr) {
1929 sock_rps_save_rxhash(sk, skb);
1930 sk_mark_napi_id(sk, skb);
1931 sk_incoming_cpu_update(sk);
1932 } else {
1933 sk_mark_napi_id_once(sk, skb);
1934 }
1935
1936 rc = __udp_enqueue_schedule_skb(sk, skb);
1937 if (rc < 0) {
1938 int is_udplite = IS_UDPLITE(sk);
1939
1940
1941 if (rc == -ENOMEM)
1942 UDP_INC_STATS(sock_net(sk), UDP_MIB_RCVBUFERRORS,
1943 is_udplite);
1944 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
1945 kfree_skb(skb);
1946 trace_udp_fail_queue_rcv_skb(rc, sk);
1947 return -1;
1948 }
1949
1950 return 0;
1951}
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
1962{
1963 struct udp_sock *up = udp_sk(sk);
1964 int is_udplite = IS_UDPLITE(sk);
1965
1966
1967
1968
1969 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
1970 goto drop;
1971 nf_reset(skb);
1972
1973 if (static_branch_unlikely(&udp_encap_needed_key) && up->encap_type) {
1974 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988 encap_rcv = READ_ONCE(up->encap_rcv);
1989 if (encap_rcv) {
1990 int ret;
1991
1992
1993 if (udp_lib_checksum_complete(skb))
1994 goto csum_error;
1995
1996 ret = encap_rcv(sk, skb);
1997 if (ret <= 0) {
1998 __UDP_INC_STATS(sock_net(sk),
1999 UDP_MIB_INDATAGRAMS,
2000 is_udplite);
2001 return -ret;
2002 }
2003 }
2004
2005
2006 }
2007
2008
2009
2010
2011 if ((is_udplite & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024 if (up->pcrlen == 0) {
2025 net_dbg_ratelimited("UDPLite: partial coverage %d while full coverage %d requested\n",
2026 UDP_SKB_CB(skb)->cscov, skb->len);
2027 goto drop;
2028 }
2029
2030
2031
2032
2033
2034
2035 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
2036 net_dbg_ratelimited("UDPLite: coverage %d too small, need min %d\n",
2037 UDP_SKB_CB(skb)->cscov, up->pcrlen);
2038 goto drop;
2039 }
2040 }
2041
2042 prefetch(&sk->sk_rmem_alloc);
2043 if (rcu_access_pointer(sk->sk_filter) &&
2044 udp_lib_checksum_complete(skb))
2045 goto csum_error;
2046
2047 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr)))
2048 goto drop;
2049
2050 udp_csum_pull_header(skb);
2051
2052 ipv4_pktinfo_prepare(sk, skb);
2053 return __udp_queue_rcv_skb(sk, skb);
2054
2055csum_error:
2056 __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
2057drop:
2058 __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
2059 atomic_inc(&sk->sk_drops);
2060 kfree_skb(skb);
2061 return -1;
2062}
2063
2064static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2065{
2066 struct sk_buff *next, *segs;
2067 int ret;
2068
2069 if (likely(!udp_unexpected_gso(sk, skb)))
2070 return udp_queue_rcv_one_skb(sk, skb);
2071
2072 BUILD_BUG_ON(sizeof(struct udp_skb_cb) > SKB_SGO_CB_OFFSET);
2073 __skb_push(skb, -skb_mac_offset(skb));
2074 segs = udp_rcv_segment(sk, skb, true);
2075 for (skb = segs; skb; skb = next) {
2076 next = skb->next;
2077 __skb_pull(skb, skb_transport_offset(skb));
2078 ret = udp_queue_rcv_one_skb(sk, skb);
2079 if (ret > 0)
2080 ip_protocol_deliver_rcu(dev_net(skb->dev), skb, -ret);
2081 }
2082 return 0;
2083}
2084
2085
2086
2087
2088bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
2089{
2090 struct dst_entry *old;
2091
2092 if (dst_hold_safe(dst)) {
2093 old = xchg(&sk->sk_rx_dst, dst);
2094 dst_release(old);
2095 return old != dst;
2096 }
2097 return false;
2098}
2099EXPORT_SYMBOL(udp_sk_rx_dst_set);
2100
2101
2102
2103
2104
2105
2106static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
2107 struct udphdr *uh,
2108 __be32 saddr, __be32 daddr,
2109 struct udp_table *udptable,
2110 int proto)
2111{
2112 struct sock *sk, *first = NULL;
2113 unsigned short hnum = ntohs(uh->dest);
2114 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
2115 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
2116 unsigned int offset = offsetof(typeof(*sk), sk_node);
2117 int dif = skb->dev->ifindex;
2118 int sdif = inet_sdif(skb);
2119 struct hlist_node *node;
2120 struct sk_buff *nskb;
2121
2122 if (use_hash2) {
2123 hash2_any = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum) &
2124 udptable->mask;
2125 hash2 = ipv4_portaddr_hash(net, daddr, hnum) & udptable->mask;
2126start_lookup:
2127 hslot = &udptable->hash2[hash2];
2128 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
2129 }
2130
2131 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
2132 if (!__udp_is_mcast_sock(net, sk, uh->dest, daddr,
2133 uh->source, saddr, dif, sdif, hnum))
2134 continue;
2135
2136 if (!first) {
2137 first = sk;
2138 continue;
2139 }
2140 nskb = skb_clone(skb, GFP_ATOMIC);
2141
2142 if (unlikely(!nskb)) {
2143 atomic_inc(&sk->sk_drops);
2144 __UDP_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
2145 IS_UDPLITE(sk));
2146 __UDP_INC_STATS(net, UDP_MIB_INERRORS,
2147 IS_UDPLITE(sk));
2148 continue;
2149 }
2150 if (udp_queue_rcv_skb(sk, nskb) > 0)
2151 consume_skb(nskb);
2152 }
2153
2154
2155 if (use_hash2 && hash2 != hash2_any) {
2156 hash2 = hash2_any;
2157 goto start_lookup;
2158 }
2159
2160 if (first) {
2161 if (udp_queue_rcv_skb(first, skb) > 0)
2162 consume_skb(skb);
2163 } else {
2164 kfree_skb(skb);
2165 __UDP_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
2166 proto == IPPROTO_UDPLITE);
2167 }
2168 return 0;
2169}
2170
2171
2172
2173
2174
2175
2176static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,
2177 int proto)
2178{
2179 int err;
2180
2181 UDP_SKB_CB(skb)->partial_cov = 0;
2182 UDP_SKB_CB(skb)->cscov = skb->len;
2183
2184 if (proto == IPPROTO_UDPLITE) {
2185 err = udplite_checksum_init(skb, uh);
2186 if (err)
2187 return err;
2188
2189 if (UDP_SKB_CB(skb)->partial_cov) {
2190 skb->csum = inet_compute_pseudo(skb, proto);
2191 return 0;
2192 }
2193 }
2194
2195
2196
2197
2198 err = (__force int)skb_checksum_init_zero_check(skb, proto, uh->check,
2199 inet_compute_pseudo);
2200 if (err)
2201 return err;
2202
2203 if (skb->ip_summed == CHECKSUM_COMPLETE && !skb->csum_valid) {
2204
2205 if (skb->csum_complete_sw)
2206 return 1;
2207
2208
2209
2210
2211
2212 skb_checksum_complete_unset(skb);
2213 }
2214
2215 return 0;
2216}
2217
2218
2219
2220
2221static int udp_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
2222 struct udphdr *uh)
2223{
2224 int ret;
2225
2226 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
2227 skb_checksum_try_convert(skb, IPPROTO_UDP, inet_compute_pseudo);
2228
2229 ret = udp_queue_rcv_skb(sk, skb);
2230
2231
2232
2233
2234 if (ret > 0)
2235 return -ret;
2236 return 0;
2237}
2238
2239
2240
2241
2242
2243int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
2244 int proto)
2245{
2246 struct sock *sk;
2247 struct udphdr *uh;
2248 unsigned short ulen;
2249 struct rtable *rt = skb_rtable(skb);
2250 __be32 saddr, daddr;
2251 struct net *net = dev_net(skb->dev);
2252
2253
2254
2255
2256 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
2257 goto drop;
2258
2259 uh = udp_hdr(skb);
2260 ulen = ntohs(uh->len);
2261 saddr = ip_hdr(skb)->saddr;
2262 daddr = ip_hdr(skb)->daddr;
2263
2264 if (ulen > skb->len)
2265 goto short_packet;
2266
2267 if (proto == IPPROTO_UDP) {
2268
2269 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
2270 goto short_packet;
2271 uh = udp_hdr(skb);
2272 }
2273
2274 if (udp4_csum_init(skb, uh, proto))
2275 goto csum_error;
2276
2277 sk = skb_steal_sock(skb);
2278 if (sk) {
2279 struct dst_entry *dst = skb_dst(skb);
2280 int ret;
2281
2282 if (unlikely(sk->sk_rx_dst != dst))
2283 udp_sk_rx_dst_set(sk, dst);
2284
2285 ret = udp_unicast_rcv_skb(sk, skb, uh);
2286 sock_put(sk);
2287 return ret;
2288 }
2289
2290 if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
2291 return __udp4_lib_mcast_deliver(net, skb, uh,
2292 saddr, daddr, udptable, proto);
2293
2294 sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
2295 if (sk)
2296 return udp_unicast_rcv_skb(sk, skb, uh);
2297
2298 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
2299 goto drop;
2300 nf_reset(skb);
2301
2302
2303 if (udp_lib_checksum_complete(skb))
2304 goto csum_error;
2305
2306 __UDP_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
2307 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
2308
2309
2310
2311
2312
2313 kfree_skb(skb);
2314 return 0;
2315
2316short_packet:
2317 net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
2318 proto == IPPROTO_UDPLITE ? "Lite" : "",
2319 &saddr, ntohs(uh->source),
2320 ulen, skb->len,
2321 &daddr, ntohs(uh->dest));
2322 goto drop;
2323
2324csum_error:
2325
2326
2327
2328
2329 net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
2330 proto == IPPROTO_UDPLITE ? "Lite" : "",
2331 &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest),
2332 ulen);
2333 __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
2334drop:
2335 __UDP_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
2336 kfree_skb(skb);
2337 return 0;
2338}
2339
2340
2341
2342
2343static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net,
2344 __be16 loc_port, __be32 loc_addr,
2345 __be16 rmt_port, __be32 rmt_addr,
2346 int dif, int sdif)
2347{
2348 struct sock *sk, *result;
2349 unsigned short hnum = ntohs(loc_port);
2350 unsigned int slot = udp_hashfn(net, hnum, udp_table.mask);
2351 struct udp_hslot *hslot = &udp_table.hash[slot];
2352
2353
2354 if (hslot->count > 10)
2355 return NULL;
2356
2357 result = NULL;
2358 sk_for_each_rcu(sk, &hslot->head) {
2359 if (__udp_is_mcast_sock(net, sk, loc_port, loc_addr,
2360 rmt_port, rmt_addr, dif, sdif, hnum)) {
2361 if (result)
2362 return NULL;
2363 result = sk;
2364 }
2365 }
2366
2367 return result;
2368}
2369
2370
2371
2372
2373
2374static struct sock *__udp4_lib_demux_lookup(struct net *net,
2375 __be16 loc_port, __be32 loc_addr,
2376 __be16 rmt_port, __be32 rmt_addr,
2377 int dif, int sdif)
2378{
2379 unsigned short hnum = ntohs(loc_port);
2380 unsigned int hash2 = ipv4_portaddr_hash(net, loc_addr, hnum);
2381 unsigned int slot2 = hash2 & udp_table.mask;
2382 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
2383 INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr);
2384 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
2385 struct sock *sk;
2386
2387 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
2388 if (INET_MATCH(sk, net, acookie, rmt_addr,
2389 loc_addr, ports, dif, sdif))
2390 return sk;
2391
2392 break;
2393 }
2394 return NULL;
2395}
2396
2397int udp_v4_early_demux(struct sk_buff *skb)
2398{
2399 struct net *net = dev_net(skb->dev);
2400 struct in_device *in_dev = NULL;
2401 const struct iphdr *iph;
2402 const struct udphdr *uh;
2403 struct sock *sk = NULL;
2404 struct dst_entry *dst;
2405 int dif = skb->dev->ifindex;
2406 int sdif = inet_sdif(skb);
2407 int ours;
2408
2409
2410 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct udphdr)))
2411 return 0;
2412
2413 iph = ip_hdr(skb);
2414 uh = udp_hdr(skb);
2415
2416 if (skb->pkt_type == PACKET_MULTICAST) {
2417 in_dev = __in_dev_get_rcu(skb->dev);
2418
2419 if (!in_dev)
2420 return 0;
2421
2422 ours = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr,
2423 iph->protocol);
2424 if (!ours)
2425 return 0;
2426
2427 sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr,
2428 uh->source, iph->saddr,
2429 dif, sdif);
2430 } else if (skb->pkt_type == PACKET_HOST) {
2431 sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr,
2432 uh->source, iph->saddr, dif, sdif);
2433 }
2434
2435 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
2436 return 0;
2437
2438 skb->sk = sk;
2439 skb->destructor = sock_efree;
2440 dst = READ_ONCE(sk->sk_rx_dst);
2441
2442 if (dst)
2443 dst = dst_check(dst, 0);
2444 if (dst) {
2445 u32 itag = 0;
2446
2447
2448
2449
2450
2451 skb_dst_set_noref(skb, dst);
2452
2453
2454
2455
2456 if (!inet_sk(sk)->inet_daddr && in_dev)
2457 return ip_mc_validate_source(skb, iph->daddr,
2458 iph->saddr, iph->tos,
2459 skb->dev, in_dev, &itag);
2460 }
2461 return 0;
2462}
2463
2464int udp_rcv(struct sk_buff *skb)
2465{
2466 return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);
2467}
2468
2469void udp_destroy_sock(struct sock *sk)
2470{
2471 struct udp_sock *up = udp_sk(sk);
2472 bool slow = lock_sock_fast(sk);
2473 udp_flush_pending_frames(sk);
2474 unlock_sock_fast(sk, slow);
2475 if (static_branch_unlikely(&udp_encap_needed_key)) {
2476 if (up->encap_type) {
2477 void (*encap_destroy)(struct sock *sk);
2478 encap_destroy = READ_ONCE(up->encap_destroy);
2479 if (encap_destroy)
2480 encap_destroy(sk);
2481 }
2482 if (up->encap_enabled)
2483 static_branch_dec(&udp_encap_needed_key);
2484 }
2485}
2486
2487
2488
2489
2490int udp_lib_setsockopt(struct sock *sk, int level, int optname,
2491 char __user *optval, unsigned int optlen,
2492 int (*push_pending_frames)(struct sock *))
2493{
2494 struct udp_sock *up = udp_sk(sk);
2495 int val, valbool;
2496 int err = 0;
2497 int is_udplite = IS_UDPLITE(sk);
2498
2499 if (optlen < sizeof(int))
2500 return -EINVAL;
2501
2502 if (get_user(val, (int __user *)optval))
2503 return -EFAULT;
2504
2505 valbool = val ? 1 : 0;
2506
2507 switch (optname) {
2508 case UDP_CORK:
2509 if (val != 0) {
2510 up->corkflag = 1;
2511 } else {
2512 up->corkflag = 0;
2513 lock_sock(sk);
2514 push_pending_frames(sk);
2515 release_sock(sk);
2516 }
2517 break;
2518
2519 case UDP_ENCAP:
2520 switch (val) {
2521 case 0:
2522 case UDP_ENCAP_ESPINUDP:
2523 case UDP_ENCAP_ESPINUDP_NON_IKE:
2524 up->encap_rcv = xfrm4_udp_encap_rcv;
2525
2526 case UDP_ENCAP_L2TPINUDP:
2527 up->encap_type = val;
2528 lock_sock(sk);
2529 udp_tunnel_encap_enable(sk->sk_socket);
2530 release_sock(sk);
2531 break;
2532 default:
2533 err = -ENOPROTOOPT;
2534 break;
2535 }
2536 break;
2537
2538 case UDP_NO_CHECK6_TX:
2539 up->no_check6_tx = valbool;
2540 break;
2541
2542 case UDP_NO_CHECK6_RX:
2543 up->no_check6_rx = valbool;
2544 break;
2545
2546 case UDP_SEGMENT:
2547 if (val < 0 || val > USHRT_MAX)
2548 return -EINVAL;
2549 up->gso_size = val;
2550 break;
2551
2552 case UDP_GRO:
2553 lock_sock(sk);
2554 if (valbool)
2555 udp_tunnel_encap_enable(sk->sk_socket);
2556 up->gro_enabled = valbool;
2557 release_sock(sk);
2558 break;
2559
2560
2561
2562
2563
2564
2565 case UDPLITE_SEND_CSCOV:
2566 if (!is_udplite)
2567 return -ENOPROTOOPT;
2568 if (val != 0 && val < 8)
2569 val = 8;
2570 else if (val > USHRT_MAX)
2571 val = USHRT_MAX;
2572 up->pcslen = val;
2573 up->pcflag |= UDPLITE_SEND_CC;
2574 break;
2575
2576
2577
2578
2579 case UDPLITE_RECV_CSCOV:
2580 if (!is_udplite)
2581 return -ENOPROTOOPT;
2582 if (val != 0 && val < 8)
2583 val = 8;
2584 else if (val > USHRT_MAX)
2585 val = USHRT_MAX;
2586 up->pcrlen = val;
2587 up->pcflag |= UDPLITE_RECV_CC;
2588 break;
2589
2590 default:
2591 err = -ENOPROTOOPT;
2592 break;
2593 }
2594
2595 return err;
2596}
2597EXPORT_SYMBOL(udp_lib_setsockopt);
2598
2599int udp_setsockopt(struct sock *sk, int level, int optname,
2600 char __user *optval, unsigned int optlen)
2601{
2602 if (level == SOL_UDP || level == SOL_UDPLITE)
2603 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
2604 udp_push_pending_frames);
2605 return ip_setsockopt(sk, level, optname, optval, optlen);
2606}
2607
2608#ifdef CONFIG_COMPAT
2609int compat_udp_setsockopt(struct sock *sk, int level, int optname,
2610 char __user *optval, unsigned int optlen)
2611{
2612 if (level == SOL_UDP || level == SOL_UDPLITE)
2613 return udp_lib_setsockopt(sk, level, optname, optval, optlen,
2614 udp_push_pending_frames);
2615 return compat_ip_setsockopt(sk, level, optname, optval, optlen);
2616}
2617#endif
2618
2619int udp_lib_getsockopt(struct sock *sk, int level, int optname,
2620 char __user *optval, int __user *optlen)
2621{
2622 struct udp_sock *up = udp_sk(sk);
2623 int val, len;
2624
2625 if (get_user(len, optlen))
2626 return -EFAULT;
2627
2628 len = min_t(unsigned int, len, sizeof(int));
2629
2630 if (len < 0)
2631 return -EINVAL;
2632
2633 switch (optname) {
2634 case UDP_CORK:
2635 val = up->corkflag;
2636 break;
2637
2638 case UDP_ENCAP:
2639 val = up->encap_type;
2640 break;
2641
2642 case UDP_NO_CHECK6_TX:
2643 val = up->no_check6_tx;
2644 break;
2645
2646 case UDP_NO_CHECK6_RX:
2647 val = up->no_check6_rx;
2648 break;
2649
2650 case UDP_SEGMENT:
2651 val = up->gso_size;
2652 break;
2653
2654
2655
2656 case UDPLITE_SEND_CSCOV:
2657 val = up->pcslen;
2658 break;
2659
2660 case UDPLITE_RECV_CSCOV:
2661 val = up->pcrlen;
2662 break;
2663
2664 default:
2665 return -ENOPROTOOPT;
2666 }
2667
2668 if (put_user(len, optlen))
2669 return -EFAULT;
2670 if (copy_to_user(optval, &val, len))
2671 return -EFAULT;
2672 return 0;
2673}
2674EXPORT_SYMBOL(udp_lib_getsockopt);
2675
2676int udp_getsockopt(struct sock *sk, int level, int optname,
2677 char __user *optval, int __user *optlen)
2678{
2679 if (level == SOL_UDP || level == SOL_UDPLITE)
2680 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
2681 return ip_getsockopt(sk, level, optname, optval, optlen);
2682}
2683
2684#ifdef CONFIG_COMPAT
2685int compat_udp_getsockopt(struct sock *sk, int level, int optname,
2686 char __user *optval, int __user *optlen)
2687{
2688 if (level == SOL_UDP || level == SOL_UDPLITE)
2689 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
2690 return compat_ip_getsockopt(sk, level, optname, optval, optlen);
2691}
2692#endif
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706__poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait)
2707{
2708 __poll_t mask = datagram_poll(file, sock, wait);
2709 struct sock *sk = sock->sk;
2710
2711 if (!skb_queue_empty(&udp_sk(sk)->reader_queue))
2712 mask |= EPOLLIN | EPOLLRDNORM;
2713
2714
2715 if ((mask & EPOLLRDNORM) && !(file->f_flags & O_NONBLOCK) &&
2716 !(sk->sk_shutdown & RCV_SHUTDOWN) && first_packet_length(sk) == -1)
2717 mask &= ~(EPOLLIN | EPOLLRDNORM);
2718
2719 return mask;
2720
2721}
2722EXPORT_SYMBOL(udp_poll);
2723
2724int udp_abort(struct sock *sk, int err)
2725{
2726 lock_sock(sk);
2727
2728 sk->sk_err = err;
2729 sk->sk_error_report(sk);
2730 __udp_disconnect(sk, 0);
2731
2732 release_sock(sk);
2733
2734 return 0;
2735}
2736EXPORT_SYMBOL_GPL(udp_abort);
2737
2738struct proto udp_prot = {
2739 .name = "UDP",
2740 .owner = THIS_MODULE,
2741 .close = udp_lib_close,
2742 .pre_connect = udp_pre_connect,
2743 .connect = ip4_datagram_connect,
2744 .disconnect = udp_disconnect,
2745 .ioctl = udp_ioctl,
2746 .init = udp_init_sock,
2747 .destroy = udp_destroy_sock,
2748 .setsockopt = udp_setsockopt,
2749 .getsockopt = udp_getsockopt,
2750 .sendmsg = udp_sendmsg,
2751 .recvmsg = udp_recvmsg,
2752 .sendpage = udp_sendpage,
2753 .release_cb = ip4_datagram_release_cb,
2754 .hash = udp_lib_hash,
2755 .unhash = udp_lib_unhash,
2756 .rehash = udp_v4_rehash,
2757 .get_port = udp_v4_get_port,
2758 .memory_allocated = &udp_memory_allocated,
2759 .sysctl_mem = sysctl_udp_mem,
2760 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
2761 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
2762 .obj_size = sizeof(struct udp_sock),
2763 .h.udp_table = &udp_table,
2764#ifdef CONFIG_COMPAT
2765 .compat_setsockopt = compat_udp_setsockopt,
2766 .compat_getsockopt = compat_udp_getsockopt,
2767#endif
2768 .diag_destroy = udp_abort,
2769};
2770EXPORT_SYMBOL(udp_prot);
2771
2772
2773#ifdef CONFIG_PROC_FS
2774
2775static struct sock *udp_get_first(struct seq_file *seq, int start)
2776{
2777 struct sock *sk;
2778 struct udp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
2779 struct udp_iter_state *state = seq->private;
2780 struct net *net = seq_file_net(seq);
2781
2782 for (state->bucket = start; state->bucket <= afinfo->udp_table->mask;
2783 ++state->bucket) {
2784 struct udp_hslot *hslot = &afinfo->udp_table->hash[state->bucket];
2785
2786 if (hlist_empty(&hslot->head))
2787 continue;
2788
2789 spin_lock_bh(&hslot->lock);
2790 sk_for_each(sk, &hslot->head) {
2791 if (!net_eq(sock_net(sk), net))
2792 continue;
2793 if (sk->sk_family == afinfo->family)
2794 goto found;
2795 }
2796 spin_unlock_bh(&hslot->lock);
2797 }
2798 sk = NULL;
2799found:
2800 return sk;
2801}
2802
2803static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
2804{
2805 struct udp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
2806 struct udp_iter_state *state = seq->private;
2807 struct net *net = seq_file_net(seq);
2808
2809 do {
2810 sk = sk_next(sk);
2811 } while (sk && (!net_eq(sock_net(sk), net) || sk->sk_family != afinfo->family));
2812
2813 if (!sk) {
2814 if (state->bucket <= afinfo->udp_table->mask)
2815 spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
2816 return udp_get_first(seq, state->bucket + 1);
2817 }
2818 return sk;
2819}
2820
2821static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos)
2822{
2823 struct sock *sk = udp_get_first(seq, 0);
2824
2825 if (sk)
2826 while (pos && (sk = udp_get_next(seq, sk)) != NULL)
2827 --pos;
2828 return pos ? NULL : sk;
2829}
2830
2831void *udp_seq_start(struct seq_file *seq, loff_t *pos)
2832{
2833 struct udp_iter_state *state = seq->private;
2834 state->bucket = MAX_UDP_PORTS;
2835
2836 return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
2837}
2838EXPORT_SYMBOL(udp_seq_start);
2839
2840void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2841{
2842 struct sock *sk;
2843
2844 if (v == SEQ_START_TOKEN)
2845 sk = udp_get_idx(seq, 0);
2846 else
2847 sk = udp_get_next(seq, v);
2848
2849 ++*pos;
2850 return sk;
2851}
2852EXPORT_SYMBOL(udp_seq_next);
2853
2854void udp_seq_stop(struct seq_file *seq, void *v)
2855{
2856 struct udp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
2857 struct udp_iter_state *state = seq->private;
2858
2859 if (state->bucket <= afinfo->udp_table->mask)
2860 spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
2861}
2862EXPORT_SYMBOL(udp_seq_stop);
2863
2864
2865static void udp4_format_sock(struct sock *sp, struct seq_file *f,
2866 int bucket)
2867{
2868 struct inet_sock *inet = inet_sk(sp);
2869 __be32 dest = inet->inet_daddr;
2870 __be32 src = inet->inet_rcv_saddr;
2871 __u16 destp = ntohs(inet->inet_dport);
2872 __u16 srcp = ntohs(inet->inet_sport);
2873
2874 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
2875 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
2876 bucket, src, srcp, dest, destp, sp->sk_state,
2877 sk_wmem_alloc_get(sp),
2878 udp_rqueue_get(sp),
2879 0, 0L, 0,
2880 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
2881 0, sock_i_ino(sp),
2882 refcount_read(&sp->sk_refcnt), sp,
2883 atomic_read(&sp->sk_drops));
2884}
2885
2886int udp4_seq_show(struct seq_file *seq, void *v)
2887{
2888 seq_setwidth(seq, 127);
2889 if (v == SEQ_START_TOKEN)
2890 seq_puts(seq, " sl local_address rem_address st tx_queue "
2891 "rx_queue tr tm->when retrnsmt uid timeout "
2892 "inode ref pointer drops");
2893 else {
2894 struct udp_iter_state *state = seq->private;
2895
2896 udp4_format_sock(v, seq, state->bucket);
2897 }
2898 seq_pad(seq, '\n');
2899 return 0;
2900}
2901
2902const struct seq_operations udp_seq_ops = {
2903 .start = udp_seq_start,
2904 .next = udp_seq_next,
2905 .stop = udp_seq_stop,
2906 .show = udp4_seq_show,
2907};
2908EXPORT_SYMBOL(udp_seq_ops);
2909
2910static struct udp_seq_afinfo udp4_seq_afinfo = {
2911 .family = AF_INET,
2912 .udp_table = &udp_table,
2913};
2914
2915static int __net_init udp4_proc_init_net(struct net *net)
2916{
2917 if (!proc_create_net_data("udp", 0444, net->proc_net, &udp_seq_ops,
2918 sizeof(struct udp_iter_state), &udp4_seq_afinfo))
2919 return -ENOMEM;
2920 return 0;
2921}
2922
2923static void __net_exit udp4_proc_exit_net(struct net *net)
2924{
2925 remove_proc_entry("udp", net->proc_net);
2926}
2927
2928static struct pernet_operations udp4_net_ops = {
2929 .init = udp4_proc_init_net,
2930 .exit = udp4_proc_exit_net,
2931};
2932
2933int __init udp4_proc_init(void)
2934{
2935 return register_pernet_subsys(&udp4_net_ops);
2936}
2937
2938void udp4_proc_exit(void)
2939{
2940 unregister_pernet_subsys(&udp4_net_ops);
2941}
2942#endif
2943
2944static __initdata unsigned long uhash_entries;
2945static int __init set_uhash_entries(char *str)
2946{
2947 ssize_t ret;
2948
2949 if (!str)
2950 return 0;
2951
2952 ret = kstrtoul(str, 0, &uhash_entries);
2953 if (ret)
2954 return 0;
2955
2956 if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN)
2957 uhash_entries = UDP_HTABLE_SIZE_MIN;
2958 return 1;
2959}
2960__setup("uhash_entries=", set_uhash_entries);
2961
2962void __init udp_table_init(struct udp_table *table, const char *name)
2963{
2964 unsigned int i;
2965
2966 table->hash = alloc_large_system_hash(name,
2967 2 * sizeof(struct udp_hslot),
2968 uhash_entries,
2969 21,
2970 0,
2971 &table->log,
2972 &table->mask,
2973 UDP_HTABLE_SIZE_MIN,
2974 64 * 1024);
2975
2976 table->hash2 = table->hash + (table->mask + 1);
2977 for (i = 0; i <= table->mask; i++) {
2978 INIT_HLIST_HEAD(&table->hash[i].head);
2979 table->hash[i].count = 0;
2980 spin_lock_init(&table->hash[i].lock);
2981 }
2982 for (i = 0; i <= table->mask; i++) {
2983 INIT_HLIST_HEAD(&table->hash2[i].head);
2984 table->hash2[i].count = 0;
2985 spin_lock_init(&table->hash2[i].lock);
2986 }
2987}
2988
2989u32 udp_flow_hashrnd(void)
2990{
2991 static u32 hashrnd __read_mostly;
2992
2993 net_get_random_once(&hashrnd, sizeof(hashrnd));
2994
2995 return hashrnd;
2996}
2997EXPORT_SYMBOL(udp_flow_hashrnd);
2998
2999static void __udp_sysctl_init(struct net *net)
3000{
3001 net->ipv4.sysctl_udp_rmem_min = SK_MEM_QUANTUM;
3002 net->ipv4.sysctl_udp_wmem_min = SK_MEM_QUANTUM;
3003
3004#ifdef CONFIG_NET_L3_MASTER_DEV
3005 net->ipv4.sysctl_udp_l3mdev_accept = 0;
3006#endif
3007}
3008
3009static int __net_init udp_sysctl_init(struct net *net)
3010{
3011 __udp_sysctl_init(net);
3012 return 0;
3013}
3014
3015static struct pernet_operations __net_initdata udp_sysctl_ops = {
3016 .init = udp_sysctl_init,
3017};
3018
3019void __init udp_init(void)
3020{
3021 unsigned long limit;
3022 unsigned int i;
3023
3024 udp_table_init(&udp_table, "UDP");
3025 limit = nr_free_buffer_pages() / 8;
3026 limit = max(limit, 128UL);
3027 sysctl_udp_mem[0] = limit / 4 * 3;
3028 sysctl_udp_mem[1] = limit;
3029 sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2;
3030
3031 __udp_sysctl_init(&init_net);
3032
3033
3034 udp_busylocks_log = ilog2(nr_cpu_ids) + 4;
3035 udp_busylocks = kmalloc(sizeof(spinlock_t) << udp_busylocks_log,
3036 GFP_KERNEL);
3037 if (!udp_busylocks)
3038 panic("UDP: failed to alloc udp_busylocks\n");
3039 for (i = 0; i < (1U << udp_busylocks_log); i++)
3040 spin_lock_init(udp_busylocks + i);
3041
3042 if (register_pernet_subsys(&udp_sysctl_ops))
3043 panic("UDP: failed to init sysctl parameters.\n");
3044}
3045